How do I convert Double[] to double[]?

Question

I\'m implementing an interface that has functionality similar to a table that can contain an types of objects. The interface specifies the following function:

Answer 1

Unfortunately you will need to loop through the entire list and unbox the Double if you want to convert it to a double[].

As far as performance goes, there is some time associated with boxing and unboxing primitives in Java. If the set is small enough, you won't see any performance issues.